Unlocking the sugar "steric gate" of DNA polymerases.
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ABSTRACT:
SUBMITTER: Brown JA
PROVIDER: S-EPMC3040255 | biostudies-literature | 2011 Feb
REPOSITORIES: biostudies-literature
Publications
Unlocking the sugar "steric gate" of DNA polymerases.
Brown Jessica A JA Suo Zucai Z
Biochemistry 20110126 7
To maintain genomic stability, ribonucleotide incorporation during DNA synthesis is controlled predominantly at the DNA polymerase level. A steric clash between the 2'-hydroxyl of an incoming ribonucleotide and a bulky active site residue, known as the "steric gate", establishes an effective mechanism for most DNA polymerases to selectively insert deoxyribonucleotides. Recent kinetic, structural, and in vivo studies have illuminated novel features about ribonucleotide exclusion and the mechanist ...[more]
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